1. Map of US 144 US watersheds used as input in the NANI dataset calculations. The Net Anthropogenic Input is calculated at the county level. We explore county-level US data for spatial patterns in the EKC, and examine the effect of social capital on pollution. We use six different estimators: (1) OLS; (2) spatial error; (3), spatial lag; (4) general spatial; (5) spatial Durbin; and (6) GWR. This approach provides parameter estimates that allow for spatial heterogeneity in the relationship between nutrient pollution and income, as well as the other explanatory variables to vary over space. As in previous studies, the core of our model examines the relationship between environmental quality and income/income 2. In this study, we have chosen nitrogen (N) which, in high concentrations, can be a serious pollutant, particularly causing eutrophication. We use the NANI (Net Anthropogenic Nitrogen Inputs) index developed by Cornell/NOAA. Our model also included explanatory variables such as a social capital index, a measure of rurality, age, a racial fragmentation index, educational attainment, Gini measure, and population change. Recent research indicates that local networks, social norms, levels of trust, and the ability to cooperate and undertake collective action (i.e. social capital) are vital to the explanation of local and regional pollution levels. Results at this stage indicate a “significant” inverted U shaped EKC. Our results also suggest that spatial variations are not statistically significant i.e. there is no spatial heterogeneity in the EKC in this model. This implies that uniform policies that incorporate income and pollution levels across the U.S. are justified. Incorporating Spatial and Social Capital Issues into the Environmental Kuznets Curve Steven C. Deller (University of Wisconsin), John M. Halstead, Patricia M. Jarema (University of New Hampshire), Ashleigh Arledge Keene (Energy Center of Wisconsin) Abstract and Importance Hypothesized Model: NANI= £ (per capita income, per capita income 2, social capital, control variables) Net Anthropogenic Nitrogen Input Howarth et al. (1996) Expected Results. The Net Anthropogenic Nitrogren Input (NANI), is used to estimate the human-induced nitrogen inputs into a U.S. watershed. NANI estimates are shown to be good predictor of riverine nitrogen export at large, U.S. county, scale. Components of the NANI dataset: ComponentDataset Atmospheric N depositionCommunity Multiscale Air Quality Model (CMAQ) (Byun and Schere 2006) Fertilizer applicationUSGS Nutrient Input Estimates Fertilizer and agricultural N fixation US Agriculture Census Crop and animal production, net food and feed imports US Agriculture Census Human consumption, netUS Census

2. Selected Paper prepared for presentation at the Agricultural & Applied Economics Association’s 2012 AAEA Annual Meeting, Seattle, Washington, August 12-14, 2012. Copyright 2012 by authors. All rights reserved. Readers may make verbatim copies of this document for non-commercial purposes by any means, provided this copyright notice appears on all such copies.